Brake drum



C. S. ASH

BRAKE DRUM l Oct. 3, 1939.

Filed Sept. 23', 1955 FlGga.

(a mm FIG.5.

IN VEN TOR CHARLES S. ASH

ATTQRNEYS Patented' oet 3,1939 Y UNITED ys'llATES 2,174,611 BRAKE DRUM Charles S. Ash, Milford, Mich., aollgnor to Keleey-Hayes Wheel Company. Detroit, Mich., a, corporation of Delaware Application September 3 Claims.

The invention relates to brake drums and has for one of its objects to provide an improved brake drum having a satisfactorily wearing surface and constructed to have the desired strength and lightness in weight. The invention has for another object .to provide a brake drum allowing for maxmum width of braking surface and minimum depth of brake drum shell. The invention has for further objects to provide a brake drum having its parts so constructed that they can be economically manufactured; to provide a brake drum having its parts so constructed that they can be readily and economically assembled; and to provide a brake drum having provision for cooling the braking surface.

These' and other objects of the invention will become apparent from the following description, takenin connection with the accompanying drawing, in which Figure l is a cross section through a brake drum showing an` embodiment of my invention;

Figure 2 is a plan view of a portion thereof;

Figure 3 is an elevation thereof;

Figures 4, and 6 are views similar to Figure 1 showing other embodiments of my invention.

Referring to Figures 1, 2 and 3, the brake drum comprises the shell I and the brake engaging element 2. The shell comprises the back 3, the annular ang'e I integral with the back and the generally radially outwardly extending annular reinforcing rib 5 integral with and extending from the free end of the annular flange. The back 3 is provided with the annular series of holes 6 providing for the passage of the means for securing the back of the wheel hub. The reinforcing rib 5 is provided with the peripheral axially extending portion 1. The shell is of relatively light weight, it being a stamping preferably formed of soft material of relatively light gauge, the gauge, however, being suflicient to enable the shell to withstand the stresses to which it is subjected during the operation of the brake drum. By. forming the shell of a stamping'. the annular flange and the reinforcing rib are thinner than the back, thereby reducing the weight o'f the shell. Furthermore, by reason of the shell being `a stamping, the shell is true and balancedwithout requiring extra machining operations.

-The brake engaging element 2 is a liner formed separately from the shell and of a material providing a satisfactorily wearing braking surface. In the present instance, this liner is formed of cast iron.l The liner has the annular portion l' 23. 1935, Serial No. 41,820

(Cl. 18S-218) 4 axial extentl greater than that of the annular flange. The liner islalso formed with the radial portion 9 which is adapted to be secured against the back l by suitable means, such as the rivets I0. T he axial extension of the annular portion l cooperates with the reinforcing rib 5 to form the axially opening groove I I for receiving an annular flange upon a backing orlbrake supporting plate, thereby forming a labyrinth seal between the brake drum and the backing or brake supporting p ate.

provide an internal braking surface yhaving an I To facilitate cooling, the annular flange 4 is provided with the annular series of holes I2- therethrough and the annular portion 8 of the 15 the entire axial extent of the annular iiange.

The external diameter of the liner is preferably such that the liner has a tight fit with the annular ange.

In the modication shown iii Figure '4, the general construction is the Asaine as that shown in Figures l, 2 and 3, with the exception that the brake engaging element or liner I3 is secured to the brake shell Il by being interlocked with the reinforcing rib I5 at the free Aend of the annular flange. More in detail, the brake engaging element or liner has intermediate the ends of its annular portion the radially outwardly extending annular portion I8 which is provided with the angularly spaced openings I1. The reinforcing rib is provided with the angularly spaced fingers I8 which extend through these openings and are crimped over against the portion I8, whereby the shell and the liner are mechanically interlocked. It will be noted that the annular portion I6 has the peripheral axially extending part I9 which cooperates with the axial extension of the liner to form an axially opening 'annular groove for use in forming a labyrinth seal with thebacking or brake supporting plate.

Figure 5 shows another construction of brake drum in which the brake engaging element or liner 20 is formed intermediate its ends with the annular radially outwardly extending rib` or flange 2|, which is directly secured against the reinforcing rib 22 of the shell by suitable means, such as the rivets 23. In this'construction the free end of the liner is formed with the radially offset annular portion .4 within which may ex. tend an annular flange'upon the backing or brake supporting plate.

Figure 6 discloses another modincation of brake drum which is similar to that shown in Figure 5, but diiers in that the annular flange 25 of the shell is of greater axial extent than the annular ilang'e'oi' the brake drum shell, shown in Figure 5. Another dierence is that of forming the brake engaging element or liner 26 with endless lands 21 and 23 at opposite ends or at the ends of the external ribs 29 for continuous engagement with the end portions of the annular flange 25.

What I claim as my invention is:

l. A brake drum, comprising a one-piece sheet metal shell having a back and annualar iiange and a reinforcing rib at the free end of said.

2. A brake drum, comprising a one-piece stamped sheet metal shell having an annular ilange, a back at one end o1' ysaid annular ilange, a reinforcing rib at the other end of said annular ange. a separately formed brake engaging element within said annular Ilange provided with a generally radially outwardly extending part having angularly spaced openings; and ilngers projecting from the reinforcing rib through said openings and having an interlocking engagement `Witl'i said radially outwardly extending part.

3. A brake comprising a sheet metal shell having an annular ilange and having a back at one end of the annular flange. a reinforcing rib at the other end of the annular flange, a cast brake engaging element within the annular Harige-provided with a generally radially outwardly extending portion having -angularly spaced openings therethrough, and lingers pro-- jectlng from the reinforcing rib through said 

